MacScan is fine. It seems to work well — but of course evaluating a security product is always difficult. If you never get spyware or malware on your machine then MacScan doesn't seem to do much; but if you do have malware and MacScan detects it then MacScan is probably invaluable.

In my case MacScan has never detected any spyware or malware. That hopefully means that I've never had any. But the frustrating thing is that I get many false positives when I run it — ie perfectly normal, safe files are reported as malware. The developers have been OK at reducing these over time... after I reported false positives then they seem to have fixed a number of them. But I continue to get some false positives, even after reporting them. Some false positives might be inevitable, but there are still too many. False positives make me wonder about other problems in the scanning engine... how do I know if it is detecting actual malware properly? I assume it is...

The relatively limited options makes this product pretty easy to use. However the features really are too limited. Some basic features are missing, such as:

* You can't save or copy the results screen (though I think you can print it, if you have a printer which I don't!). So every time I want to report another false positive to them, I have to type out the details by hand. Being unable to copy the results makes it hard to find out more on the problem; for example you can't copy the name of the malware and paste it into Google. Frustrating!

* No way of excluding false positives. There is a handful of files that get marked as spyware every time, even though I know they are definitely safe. But the only option I am given is to isolate/delete the files; there is no option to mark it as 'safe' or 'ignore' so that it doesn't get picked up again and again.

* Limited information in results. MacScan picks up tracking cookies, such as those from advertising networks on the web. But the results only tell you the domain and that it is a tracking cookie — not what the cookie contains, not how old it is, not even which browser the cookie was found in (is it Safari? Firefox? Chrome? Opera?).

* No incremental scan. It typically takes me two days to run a MacScan 'quick scan', probably due to the large number of files I have — I'm a developer and I have over ten million files in my personal folders. With no incremental scan, MacScan has to rescan everything from the start each time. So the result is that I rarely run it — I don't often have two days spare when I can let MacScan run. If I restart the computer in that time, the scan is lost and it starts again from the start. If incremental scanning was supported, I probably use MacScan regularly instead of extremely rarely.